What Happens to Your Body When You Eat Junk Food?

April 29, 2015

Story at-a-glance

When men ate a junk-food diet, their muscles’ ability to oxidize glucose was disrupted in just five days’ time

If you lose this key player in glucose metabolism it could pave the way for insulin resistance, diabetes, and other health problems

By Dr. Mercola

If you overdo it on pizza, macaroni and cheese, chips, and ice cream, you might worry about what it's going to do to your thighs or mid-section. But binging on junk food isn't only a matter of weight gain. It might have far more serious repercussions than that.

People who ate a diet focused on macaroni and cheese, processed lunchmeat, sausage biscuits, mayonnaise, and microwavable meals with unhealthy fats, for example, showed serious negative changes to their metabolism after just five days.

After eating the junk-food diet, the study participants (12 healthy college-aged men) muscles' lost the ability to oxidize glucose after a meal, which could lead to insulin resistance down the road.1

What Happens to Your Metabolism After Five Days of Junk Food

Even though their caloric intake remained unchanged, when men ate a junk-food diet their muscles' ability to oxidize glucose was disrupted in just five days' time. This is a significant change, because muscle plays an important role in clearing glucose from your body after a meal.

Under normal circumstances, your muscles will either break down the glucose or store it for later use. Your muscles make up about 30 percent of your body weight, so if you lose this key player in glucose metabolism it could pave the way for diabetes and other health problems.2 As reported by TIME:3

"'The normal response to a meal was essentially either blunted or just not there after five days of high-fat feeding,' [Matthew] Hulver, [PhD, department head of Human Nutrition, Food, and Exercise at Virginia Tech Hulver] says.

Before going on a work-week's worth of a fatty diet, when the men ate a normal meal they saw big increases in oxidative targets four hours after eating.

That response was obliterated after the five-day fat infusion. And under normal eating conditions, the biopsied muscle used glucose as an energy source by oxidizing glucose. 'That was essentially wiped out after,' he says. 'We were surprised how robust the effects were just with five days.'"

Just One Bad Meal Can Mess with Your Health

Morgan Spurlock's documentary Super Size Me was one of the first to vividly demonstrate the consequences of trying to sustain yourself on a diet of fast food. After just four weeks, Spurlock's health had deteriorated to the point that his physician warned him he was putting his life in serious jeopardy if he continued the experiment.

But as the featured study showed, it doesn't take a virtual month to experience the health effects of a poor diet. In fact, the changes happen after just one meal, according to research published in the Journal of the American College of Cardiology.4

When you eat a meal high in unhealthy fats and sugar, the sugar causes a large spike in your blood-sugar levels called "post-prandial hyperglycemia." In the long term this can lead to an increased risk of heart attack, but there are short-term effects as well, such as:

Your tissue becomes inflamed (as occurs when it is infected)

Your blood vessels constrict

Damaging free radicals are generated

Your blood pressure may rise higher than normal

A surge and drop in insulin may leave you feeling hungry soon after your meal

The good news is that eating a healthy meal helps your body return to its normal, optimal state, even after just one. Study author James O'Keefe of the Mid America Heart Institute in Kansas City, Missouri told TIME:5

"Your health and vigor, at a very basic level, are as good as your last meal."

See Inside Your Stomach After a Meal of Instant Meals…

Dr. Braden Kuo of Massachusetts General Hospital used a pill-sized camera to see what happens inside your stomach and digestive tract after you eat ramen noodles, one common type of instant noodles. The results were astonishing…

In the video above, you can see ramen noodles inside a stomach. Even after two hours, they are remarkably intact, much more so than the homemade ramen noodles, which were used as a comparison. This is concerning for a number of reasons.

For starters, it could be putting a strain on your digestive system, which is forced to work for hours to break down this highly processed food (ironically, most processed food is so devoid of fiber that it gets broken down very quickly, interfering with your blood sugar levels and insulin release).

When food remains in your digestive tract for such a long time, it will also impact nutrient absorption, but, in the case of processed ramen noodles, there isn't much nutrition to be had. Instead, there is a long list of additives, including the toxic preservative tertiary-butyl hydroquinone (TBHQ).

This additive will likely remain in your stomach along with the seemingly invincible noodles, and no one knows what this extended exposure time may do to your health. Common sense suggests it's not going to be good…

Eating Processed Foods Linked to Chronic Disease

Research published in the Journal of Nutrition found that women who consumed more instant noodles had a significantly greater risk of metabolic syndrome than those who ate less, regardless of their overall diet or exercise habits.6

Past research also analyzed overall nutrient intake between instant-noodle consumers and non-consumers, and found, as you might suspect, that eating instant noodles contributes little value to a healthy diet.

The instant-noodle consumers had a significantly lower intake of important nutrients like protein, calcium, phosphorus, iron, potassium, vitamin A, niacin, and vitamin C compared with non-consumers.7 Those who ate instant noodles also had an excessive intake of energy, unhealthy fats, and sodium (just one package may contain 2,700 milligrams of sodium).8

Not to mention, refined carbohydrates like breakfast cereals, bagels, waffles, pretzels, and most other processed foods quickly break down to sugar in your body. This increases your insulin and leptin levels, and contributes to insulin resistance, which is the primary underlying factor of nearly every chronic disease and condition known to man, including weight gain.

Not only that, but remember… when you eat junk food you are not just feeding yourself… you’re feeding your microbiome, too, and in so doing altering its construction for better or worse. Your body’s diverse army of microbes is responsible for many crucial biological processes, from immunity to memory to mental health, so feeding it wisely, with fresh unprocessed and naturally fermented foods, is crucial to your overall health and well-being.

Is Junk Food as Dangerous as Cigarettes?

In the US, about one-quarter to one-third of adults fall into the obese category. A staggering two-thirds of Americans are overweight, and poor diet is in large part to blame. Last year, UN Special Rapporteur on the right to food, Olivier De Schutter, said that "obesity is a bigger global health threat than tobacco use," and that this fact isn't taken as seriously as it should be. His statements were delivered at the opening of the 2014 World Health Organization's annual summit. De Schutter ultimately wants nations to join forces to place stricter regulations on unhealthy foods:9

"Just as the world came together to regulate the risks of tobacco, a bold framework convention on adequate diets must now be agreed," he said. 'The Special Rapporteur has previously agitated for greater governmental action on junk foods, including taxing unhealthy products, regulating fats and sugars, cracking down on advertising for junk food, and rethinking agricultural subsidies that make unhealthy food cheaper,' Time Magazine noted. 'Governments have been focusing on increasing calorie availability,' he said, 'but they have often been indifferent to what kind of calories are offered, at what price, to whom they are made available, and how they are marketed.'"

The idea that being overweight can be more harmful than smoking is likely to make many balk, considering how "normal" it has become to carry around extra pounds, but in terms of overall health effects and subsequent health care costs, it's likely true. For example, data collected from over 60,000 Canadians show that obesity leads to more doctor visits than smoking.10

Further, according to a report by The McKinsey Global Institute, the global cost of obesity is now $2 trillion annually, which is nearly as much as the global cost of smoking ($2.1 trillion) and armed violence (including war and terrorism, which also has a global cost of $2.1 trillion).11 For comparison, alcoholism costs are $1.4 trillion annually, road accidents cost $700 billion, and unsafe sex costs $300 billion. What's more, if current trends continue, the McKinsey report estimates that nearly half of the world's adult population will be overweight or obese by 2030.

Junk Food Is Incredibly Addictive

Your body is designed to naturally regulate how much you eat and the energy you burn. But food manufacturers have figured out how to over-ride these intrinsic regulators, designing processed foods that are engineered to be "hyper-rewarding." According to the "food reward hypothesis of obesity," processed foods stimulate such a strong reward response in our brains that it becomes very easy to overeat. One of the guiding principles for the processed food industry is known as "sensory-specific satiety."

Investigative reporter Michael Moss describes this as "the tendency for big, distinct flavors to overwhelm your brain."12 The greatest successes, whether beverages or foods, owe their "craveability" to complex formulas that pique your taste buds just enough, without overwhelming them, thereby overriding your brain's inclination to say "enough." In all, potato chips are among the most addictive junk foods on the market, containing all three "bliss-inducing" ingredients: sugar (from the potato), salt, and fat. Further, as reported by TIME:13

"Studies suggest that fatty, sugary foods promote excretion of the stress hormone cortisol, which seems to further stimulate appetite for calorie-dense foods. And the big post-meal spikes in blood sugar are more likely in people who don't exercise or those who carry weight around their abdomen. All of it makes it tough for people to stop eating junk food once they're in the habit. 'The more you eat it the more you crave it. It becomes a vicious cycle,' says O'Keefe."

And while food companies abhor the word "addiction" in reference to their products, scientists have discovered that sugar, in particular, is just that. In fact, sugar is more addictive than cocaine. Research published in 2007 showed that 94 percent of rats that were allowed to choose mutually-exclusively between sugar water and cocaine, majority chose sugar.14 Even rats that were addicted to cocaine quickly switched their preference to sugar, once it was offered as a choice. The rats were also more willing to work for sugar than for cocaine.

The researchers speculate that the sweet receptors (two protein receptors located on the tongue), which evolved in ancestral times when the diet was very low in sugar, have not adapted to modern times' high-sugar consumption. Therefore, the abnormally high stimulation of these receptors by sugar-rich diets generates excessive reward signals in your brain, which have the potential to override normal self-control mechanisms and thus lead to addiction.

Does Junk Food Have a Hold on You? How to Break Free

Replacing processed foods with homemade meals made from scratch using whole ingredients is an ideal and important way to ensure optimal nutrition. This will automatically cut out the vast majority of refined sugars, processed fructose, preservatives, dyes, other nasty chemicals, and many addictive ingredients from your diet. This will allow your body to depend less on sugar and more on fat as its primary fuel—provided you eat enough healthy fat, that is.

As a result, you will no longer crave sugar to keep you going. The key elements for a healthy diet that can help kick your junk food cravings to the curb are the following. For a comprehensive guide, please see my free optimized nutrition plan:

◦ As much high-quality healthy fat as you want (saturated and monounsaturated). Many would benefit from getting as much as 50-85 percent of their daily calories from healthy fats. While this may sound like a lot, consider that, in terms of volume, the largest portion of your plate would be vegetables, since they contain so few calories.

Fat, on the other hand, tends to be very high in calories. For example, just one tablespoon of coconut oil is about 130 calories—all of it from healthy fat. Good sources include:

Planning Your Meals Is Key

Ditching processed foods requires that you plan your meals in advance, but if you take it step-by-step as described in my nutrition plan, it's quite possible, and manageable, to painlessly remove processed foods from your diet. You can try scouting out your local farmer's markets for in-season produce that is priced to sell, and planning your meals accordingly, but you can also use this same premise with supermarket sales. You can generally plan a week of meals at a time, making sure you have all ingredients necessary on hand, and then do any prep work you can ahead of time so that dinner is easy to prepare if you're short on time (and you can use leftovers for lunches the next day).

Finally, if you're an emotional eater, I highly recommend using the Emotional Freedom Technique (EFT). EFT is simple and effective, and can rapidly help you eliminate your food cravings naturally.

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